Union Club, pre-1890.

Established in 1834, the Union Club of New York City is the oldest men’s social club in the city. The origins of a number of New York's other private clubs can be traced to this organization. The Knickerbocker, Brook and Metropolitan Clubs were offshoots. Its best known descendant is the Union League Club, founded by Union Club members during the Civil War who were displeased with the club's unwillingness to dismiss its Confederate members.

The Union Club has occupied six buildings over its 183-year history. The pictured building, at the northwest corner of 21st Street and Fifth Avenue, was first building constructed expressly as club headquarters. Completed in 1855, the club moved into their first permanent home in April of that year. (The previous locations were all on Broadway, Nos. 343, 376, and 691.) An impressive mansion surrounded by residential buildings (full of likewise wealthy citizens) when built, by the turn of the century the nature of the neighborhood had changes much to the chagrin of the Club members. In 1900, they purchased a plot of land on Fifth Avenue and 51st Street for $700,000 (about $16 million in today's economy). In 1903 the Club officially moved out of their 21st Street building into a new club house designed by Cass Gilbert (or John Du Fais, or both, the attribution is a little murky).